import java.util.Scanner;

public class Text {

    public static void main(String[] args) {
        System.out.println(fun3("Hello"));


    }

    public static String fun3(String s) {
        if (s == null || s.length() == 0) {
            return null;
        }
        StringBuilder stringBuilder = new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            if ('A' < s.charAt(i) &&  s.charAt(i) < 'Z' ) {
                char n = (char) (s.charAt(i) + 32);
                stringBuilder.append(n);
            }else {
                stringBuilder.append(s.charAt(i));
            }

        }
        return  stringBuilder.toString();
    }

    public static int reWord(String s) {
        if (s == null || s.isEmpty()) {
            return 0;
        }

        String[] arr = s.split(" ");
        int count = 0;
        for (int i = 0; i < arr.length; i++) {
            if (arr[i].isEmpty()) {
                continue;
            }
            count++;
        }
        System.out.println(arr.length);
        System.out.println("===========");
        return count;
    }


    public static String fun2(String s) {
        return s.toLowerCase();
    }

    public static int fun() {
        int[] arr = new int[26];
        Scanner scanner = new Scanner(System.in);
        String str = scanner.nextLine();
        for (int i = 0; i < str.length(); i++) {
            arr[str.charAt(i) - 'a']++;
        }

        for (int i = 0; i < str.length(); i++) {
            for (int j = 0; j < arr.length; j++) {
                if (arr[str.charAt(i) - 'a'] == 1) {
                    return i;
                }
            }
        }
        return -1;
    }
}
